Antibacterial Dentifrice Exhibiting Antiplaque and Breath Freshening Properties

ABSTRACT

A dual component antiplaque oral composition having antimalodor properties in which a first component contains an antibacterial agent and the second component contains a proteolytic enzyme, the first and second components are simultaneously combined for application to the teeth, the first and second components being physically segregated prior to use, the components when mixed upon application to teeth providing substantially antiplaque effect with superior antimalodor properties.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to an oral care composition which containsa nonionic antibacterial compound effective in retarding bacterialplaque accumulation on teeth and more particularly to a dual componentdentifrice composition containing an antibacterial compound incombination with an enzyme which achieves plaque reduction with superiorbreath freshening characteristics.

2. The Prior Art

Halitosis, the technical term for bad breath, or Fetor ex Ons, is anundesirable condition. As a matter of fact, everyone, excluding the veryyoung, occasionally has bad breath, with approximately 25% suffering ona regular basis and the problem tends to get worse and more frequent asone gets older. The problem seems to be evenly split between men andwomen. Bad breath results when proteins from the food we eat and salivadebris are broken down by bacteria. Even the cleanest mouth hostsmillions of bacteria which have the potential to decompose theseprotein-containing particles left in the mouth. The tongue, with itsfissures and large, bumpy surface area, retains considerable quantitiesof food and debris that support and protect a large bacterialpopulation. Under low oxygen condition, this bacterial population formsfoul smelling products, called volatile sulfur compounds (VSC)—such ashydrogen sulfide (“rotten eggs”) and methyl mercaptans (“skunk smell”)and other odorous and bad tasting compounds. Up to 80-90% of bad breaththat originates in the mouth is by this mechanism.

Dental plaque or plaque bio-film is a soft deposit that forms on teethand is comprised of an accumulation of bacteria and salivary as well asfood by-products. Plaque adheres tenaciously at the points ofirregularity or discontinuity, e.g., on rough calculus surfaces, at thegum line, on tongue surface and within crevices. and the like. Besidesbeing unsightly, plaque is implicated in the occurrence of gingivitisand other forms of periodontal disease.

Bacteria thrive on the tongue. For the most part, the bacteria are apart of a protective bio-film that essentially renders them resistant tomost treatments. Few people clean their tongue after brushing, eventhough it's been shown that as much as 50 percent of the mouth'sbacteria can be found here. Additionally, for many people, brushing orscraping the tongue is difficult because of the gag reflex. Therefore,cleaning the tongue non-mechanically is highly desirable for those whoare unable to do so with a mechanical device.

A wide variety of antibacterial agents have been suggested in the art toretard plaque formation and the oral infections and dental diseaseassociated with plaque formation. For example, nonionic antibacterialcompounds such as Triclosan are well known to the art for theirantibacterial activity and have been used in oral compositions tocounter plaque formation by bacterial accumulation in the oral cavity.

In spite of the extensive prior art relating to antibacterial dentifricecompositions, there is still a need in the art to formulate a dentifriceproduct capable of delivering an antibacterial agent effective in theretardation of bacterial plaque accumulation on teeth, as well as on thetongue, without inhibiting the bioavailability of the antibacterialcompound. The delivery of the antibacterial compound to the tongue willallow for effective control of bad breath.

SUMMARY OF THE INVENTION

The present invention encompasses a dual component dental compositionwhich when applied to teeth contains a combination of a nonionicantibacterial compound, and an enzyme ingredient whereby reduction ofplaque accompanied by a superior antimalodor benefit is accomplishedduring tooth brushing.

The present invention is based upon the discovery that when a separatelymaintained first nonionic antibacterial compound containing dentalcomponent and a second enzyme containing dentifrice component aresimultaneously combined and thereafter applied to the surface of theteeth, undiminished antiplaque efficacy is unexpectedly obtained with asuperior retardation of oral cavity malodor when the teeth are brushedwith the combined components.

In one embodiment of the present invention, a dual component dentifricecomposition of the present invention is provided being comprised ofseparate nonionic antibacterial compound and enzyme containingdentifrice components which are housed in a container wherein thecomponents are maintained separate from each other and are not combinedand admixed until simultaneous application to teeth is to be performedby the user as by brushing. Unexpectedly, when the separately maintaineddental components are contacted with each other immediately prior toapplication to teeth, there is obtained undiminished antiplaque efficacyof the nonionic antibacterial compound accompanied by an enhancedantimalodor benefit.

The dual component dentifrice composition of the present invention wasfound to significantly reduce total bacteria on the tongue. Even morespecifically, this dual component dentifrice combination was found tosignificantly reduce the level of bacterial species on the tonguesurface responsible for the evolution of oral malodor up to five hourspost brushing when compared to a clinically proven commercial toothpastecontaining Triclosan.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

Nonionic Antibacterial Agent

Nonionic antibacterial agents used in the practice of the presentinvention include halogenated diphenyl ether compounds such as2,4,4′-trichloro-2′-hydroxydiphenyl ether (Triclosan) and2,2′-dihydroxy-5,5′-dibromodiphenyl ether. Other useful nonionicantibacterial agents include phenolic compounds including phenol and itshomologs, mono and polyalkyl and aromatic halophenols, resorcinol andits derivatives and bisphenolic compounds, such phenolic compounds beingmore fully disclosed in U.S. Pat. No. 5,368,844, the disclosure of whichis incorporated herein by reference.

The nonionic antibacterial agent is included in the dentifricecomposition at a concentration of about 0.10 to about 1.5% by weight andpreferably about 0.3 to about 1.2% by weight.

Abrasives

Abrasives preferred for use the practice of the present inventioninclude silica materials and particularly silica gels and precipitatedamorphous silica having an oil absorption value of less than 100 cc/100g silica and preferably in the range of from about 45 cc/100 g to lessthan about 70 cc/100 g silica. These silicas are colloidal particleshaving an average particle size ranging from about 3 microns to about 12microns, and more preferably between about 5 to about 10 microns and apH range from 4 to 10 preferably 6 to 9 when measured as a 5% by weightslurry.

Oil absorption values are measured using the ASTM Rub-Out Method D281.The low oil absorption silica abrasive is present in the oral carecompositions of the present invention at a concentration of about 5 toabout 40% by weight and preferably about 10 to about 30% by weight.

Low oil absorption silica abrasives particularly useful in the practiceof the present invention are marketed under the trade designationSylodent XWA by Davison Chemical Division of W.R. Grace & Co.,Baltimore, Md. 21203. Sylodent 650 XWA, a silica hydrogel composed ofparticles of colloidal silica having a water content of 29% by weightaveraging from about 7 to about 10 microns in diameter, and an oilabsorption of less than 70 cc/100 g of silica is a preferred example ofa low oil absorption silica abrasive useful in the practice of thepresent invention.

Another low oil absorption silica abrasive particularly useful in thepractice of the present invention is marketed under the tradedesignation DP-105 by J.M. Huber Chemicals Division, Havre de Grace, Md.21078 is a precipitated amorphous silica having an average particle sizedistribution from 5 to 12 microns and an oil absorption in the range of50 to 70 cc/100 g.

Other abrasives which may be used in the practice of the presentinvention include precipitated silicas having a mean particle size of upto about 20 microns, such as Zeodent 115, marketed by J.M. HuberChemicals Division, Havre de Grace, Md. 21078, or Sylodent 783 marketedby Davison Chemical Division of W.R. Grace & Company, sodiummetaphosphate, potassium metaphosphate, tricalcium phosphate, dihydrateddicalcium phosphate, aluminum silicate, calcined alumina, bentonite orother siliceous materials, or combinations thereof.

The abrasive materials may be used individually as the sole abrasive inpreparing the dental composition of the present invention or incombination with other known dentifrice abrasives. The total quantity ofabrasive present in the dentifrice compositions of the present inventionis at a level of from about 5% to about 60% by weight, preferably fromabout 10% to about 55% by weight when the dentifrice composition is atoothpaste.

Enzymes

The enzymes useful in the practice of the present invention includeprotein substances within the class of proteases, which breakdown orhydrolyze proteins (proteases). These proteolytic enzymes are obtainedfrom natural sources or by the action of microorganisms having anitrogen source and a carbon source. Examples of proteolylic enzymesuseful in the practice of the present invention include papain,bromelain, chymotrypsin, ficin and alcalase.

Papain obtained from the milky latex of the Papaya tree is theproteolytic enzyme preferred for use in the practice of the presentinvention and is incorporated in the oral care composition of thepresent invention in an amount of about 0.1 to about 10% by weight andpreferably about 0.5 to about 5% by weight, such papain having anactivity of 150 to 300 MCU per milligram as determined by the Milk ClotAssay Test of the Biddle Sawyer Group (see J. Biol. Chem., vol. 121,pages 737-745).

An additional enzyme which is formulated in combination with theprotease enzyme papain is glucoamylase. Glucoamylase is a saccharifyingglucoamylase of Aspergillus niger origin cultivated by fermentation.This enzyme can hydrolyze both the alpha-D-1,6 glucosidic branch pointsand the alpha-1,4 glucosidic bonds of glucosyl oligosaccharides. Theproduct of this invention comprises about 0.001 to 2% of thecarbohydrase and preferably about 0.01 to 0.55% by weight. Additionalcarbohydrases useful in accordance with this invention are glucoamylase,alpha and beta-amylase, dextranase and mutanase.

Other enzymes which may be used in the practice of the present inventioninclude other carbohydrases such as alpha-amylase, beta-amylase,dextranase and mutanase and lipases such as plant lipase, gastriclipase, pancreatic lipase, pectinase, tannase lysozyme and serineproteases.

The lipase enzyme is derived from a select strain of Aspergillus niger,exhibiting random cleaving of the 1,3 positions of fats and oils. Theenzyme has maximum lipolytic activity at pH 5.0 to 7.0 when assayed witholive oil. The lipase may be included in the dentifrice composition at aconcentration of about 0.010 to about 5.0% by weight and preferablyabout 0.02 to about 0.10% by weight.

The presence of tannase enzyme can be further beneficial in facilitatingthe breakdown of extrinsic stain. Tannase enzymes have been purifiedfrom Aspergillus niger and Aspergillus allianceus and are useful in thehydrolysis of tannins, known to discolor the tooth surface.

Other suitable enzymes which can comprise the present invention includelysozyme, derived from egg white, which contains a single polypeptidechain crosslinked by four disulfide bonds having a molecular weight of14,600 daltons. The enzyme can exhibit antibacterial properties byfacilitating the hydrolysis of bacterial cell walls cleaving theglycosidic bond between carbon number 1 of N-acetylmurarnic acid andcarbon number 4 of N-acetyl-D-glucosamine, which in vivo, arepolymerized to form the cell wall polysaccharide. Additionally,pectinase, an enzyme that is present in most plants, facilitates thehydorlysis of the polysaccharide pectin into sugars and galacturonicacid.

Dentifrice Vehicle

The orally-acceptable dentifrice vehicle used to prepare the dentifricecomposition comprises a water-phase, containing a humectant therein. Thehumectant is preferably glycerin, sorbitol, xylitol, and/or propyleneglycol of molecular weight in the range of 200 to 1,000. Otherhumectants, such as polyethylene glycol, and mixtures thereof may alsobe employed. The humectant concentration typically totals about 5 toabout 70% by weight of the oral composition.

Reference hereto to sorbitol refers to the material typicallycommercially available as a 70% aqueous solution. Water is presenttypically in amount of at least about 10% by weight, and generally about15 to 30% by weight of the oral composition. Water employed in thepreparation of commercially suitable toothpastes should preferably bedeionized and free of organic impurities. These amounts of water includethe free water which is added plus that which is introduced with othermaterials such as with sorbitol.

The dentifrice compositions of the present invention can contain avariety of optional dentifrice ingredients. As described below, suchoptional ingredients can include, but are not limited to, thickeningagents, surfactants, antitartar agents. a source of fluoride ions, asynthetic anionic polycarboxylate, a flavoring agent, antitartar andcoloring agents.

Thickening Agents

Thickeners used in the compositions of the present invention includenatural and synthetic gums and colloids. Suitable thickeners includenaturally occurring polymers such as carrageenans, xanthan gum,polyglycols of varying molecular weights sold under the tradenamePolyox, and polyvinylpyrrolidone. Compatible inorganic thickenersinclude amorphous silica compounds which function as thickening agentsand include colloidal silicas compounds available under the tradedesignation Cab-o-sil manufactured by Cabot Corporation and distributedby Lenape Chemical, Bound Brook, N.J.; Zeodent 165 from J.M. HuberChemicals Division, Havre de Grace, Md. 21078; and Sylodent 15,available from Davison Chemical Division of W.R. Grace Corporation,Baltimore, Md. 21203. Other inorganic thickeners include natural andsynthetic clays such as hectorite clays, lithium magnesium silicate(laponite) and magnesium aluminum silicate (Veegum).

The thickening agent is present in the dentifrice composition in amountsof about 0.1 to about 10% by weight, preferably about 0.5 to about 4.0%by weight.

Surfactants

Surfactants are used in the compositions of the present invention toachieve increased prophylactic action and render the dentifricecompositions more cosmetically acceptable. The surfactant is preferablya detersive material that imparts to the composition detersive andfoaming properties.

Anionic surfactants such as higher alkyl sulfates such as sodium laurylsulfate are not compatible with enzymes. Anionic surfactants denatureenzyme and cause loss of activity. As a result, it is important to thepractice of the present invention to use a surfactant or combination ofsurfactants that are compatible with the enzymes present in thetoothpaste formulation and provide the requisite foamingcharacteristics. Examples of enzyme compatible surfactants includenonanionic polyoxyethylene surfactants such as Pluronic F127, Polyoxamer407, Steareth 30, Polysorbate 20, and amphoteric surfactants such ascocamidopropyl betaine and cocamidopropyl betaine lauryl alucoside.Preferred surfactants include a combination of pluronic F127, Polyoxamer407, Polysorbate 20, and cocamidopropyl betaine at a total surfactantconcentration in the dentifrice composition of between about 2 to about10% by weight and preferably between about 3.5 to about 6.5% by weightat weight ratios of 2.5 Polyaxomer 407, 2.5 PEG-40 castor oil, 3.3Polysorbate-20 and 1.0 cocamidopropyl betaine.

Fluoride and Other Active Agents

The dentifrice composition of the present invention may also contain asource of fluoride ions or fluorine-providing component, as anticariesagent in amount sufficient to supply about 25 ppm to 5,000 ppm offluoride ions and include inorganic fluoride salts, such as solublealkali metal salts. For example, preferred fluoride sources which arecompatible with enzymes present in the composition are sodium fluoride,potassium fluoride, sodium fluorosilicate, ammonium fluorosilicate, aswell as tin fluorides, such as stannous fluoride and stannous chloride.Sodium fluoride is preferred.

In addition to fluoride compounds, there may also be included antitartaragents such as pyrophosphate salts including dialkali or tetraalkalimetal pyrophosphate salts such as Na₄P₂O₇, K₄P₂O₇, Na₂K₂P₂O₇, Na₂H₂P₂O₇and K₂H₂P₂O₇ sodium tripolyphosphate, long chain polyphosphates such assodium hexametaphosphate and cyclic phosphates such as sodiumtrimetaphosphate. These antitartar agents are included in the dentifricecomposition at a concentration of about 1 to about 5% by weight.

Enzyme Stabilizing Agents

The dentifrice composition of the present invention may also containingredients that stabilize enzymes in a dentifrice environment. Thesestabilizers protect the enzyme from inactivation by chelating metalimpurities present in the dentifrice composition. Chelating agentsinclude, ethylene diamine tetraacetic acid (EDTA) and sodium gluconateat concentrations between 0.01 and 1%, preferably between 0.1 and 0.5%.Other stabilizers may also prevent oxidation of amino acids, such ascysteine, that are critical for enzyme activity. Examples of agents thatstabilize the enzyme against oxidation include sodium bisulfite, metalgallates, sodium stannate and ascorbic acid at concentrations betweenabout 0.1 and about 1.5%, preferably between about 0.3 and about 0.75%.

Anionic Polycarboxylate

Synthetic anionic polycarboxylates may also be used in the dentifricecompositions of the present invention as an efficacy enhancing agent forany antibacterial, antitartar or other active agent within thedentifrice composition. Such anionic polycarboxylates are generallyemployed in the form of the free acids or preferably partially or morepreferably fully neutralized water-soluble alkali metal (e.g. potassiumand preferably sodium) or ammonium salts. Preferred are 1:4 to 4:1copolymers of maleic anhydride or acid with another polymerizableethylenically unsaturated monomer, preferably methylvinylether/maleicanhydride having a molecular weight (M.W.) of about 30,000 to about1,800,000 most preferably about 30,000 to about 700,000. Examples ofthese copolymers are available from GAF Corporation under the tradenameGantrez, e.g. AN 139 (M.W. 500,000), AN 119 (M.W. 250,000); S-97Pharmaceutical Grade (M.W. 700,000), AN 169 (M.W. 1,200,000-1,800,000),and AN 179 (M.W. above 1,800,000); wherein the preferred copolymer isS-97 Pharmaceutical Grade (M.W. 700,000).

When present, the anionic polycarboxylates is employed in amountseffective to achieve the desired enhancement of the efficacy of anyantibacterial, antitartar or other active agent within the dentifricecomposition. Generally, the anionic polycarboxylates is present withinthe dentifrice composition from about 0.05% to about 4% by weight,preferably from about 0.5% to about 2.5% by weight.

Flavor

The dentifrice composition of the present invention may also contain aflavoring agent. Flavoring agents that are used in the practice of thepresent invention include essential oils as well as various flavoringaldehydes, esters, alcohols, and similar materials. Examples of theessential oils include oils of spearmint, peppermint, wintergreen,sassafras, clove, sage, eucalyptus, marjoram, cinnamon, lemon, lime,grapefruit, and orange. Also useful are such chemicals as menthol,carvone, and anethole. Of these, the most commonly employed are the oilsof peppermint and spearmint.

The flavoring agent is incorporated in the dentifrice composition at aconcentration of about 0.1 to about 5% by weight and preferably about0.5 to about 1.5% by weight.

Other Ingredients

Various other materials may be incorporated in the dentifricecompositions of this invention, including desensitizers, such aspotassium nitrate; whitening agents; preservatives; silicones; andchlorophyll compounds. These additives, when present, are incorporatedin the dentifrice composition in amounts which do not substantiallyadversely affect the properties and characteristics desired,

A striped dentifrice product is obtained in accordance with the practiceof the present invention wherein colorants of contrasting colors areincorporated in each of the dentifrice components used in the practiceof the present invention, the colorants being pharmacologically andphysiologically nontoxic when used in the suggested amounts. Colorantsused in the practice of the present invention include pigments and dyes.

To prepare the separate dentifrice components of the present invention,for example as in the preparation of the dentifrice component containingthe nonionic antibacterial compound, the humectant and polymer binderare dispersed in a conventional mixer until the mixture becomes a welldispersed slurry which is smooth in appearance, after which water isadded. This mixture is heated to 100-130° F. and mixed for 10 to 30minutes producing a homogeneous gel phase. Sweetener and color are addedand mixed for 20 minutes. The mixture is transferred to a vacuum mixerand the abrasive is added and mixed for 10 to 30 minutes at high speedunder a vacuum in the range of 5 to 100 millimeter of mercury pressure,preferably 5 to 50 mm Hg, providing a homogeneous mixture. As the finalstage the flavor and antibacterial compound are added followed by anadditional 20 minute mixing under vacuum.

For the preparation of the enzyme containing dentifrice component, thepolymeric binder is dispersed in humectant to form a smooth dispersedslurry. To this dispersion is added water, containing dissolvedsynthetic clay, salts and the sweetener. The resulting continuous phaseis mixed under high speed for a period of no less than 20 minutes. Tothe resulting homogeneous continuous phase, silica abrasive is slowlyadded, along with the thickening silica and mixed under vacuum in therange of 5 to 100 mm of mercury for a period of 20 minutes. At thisstage, the color, surfactants and enzyme ingredients are added and mixedunder high speed for 10 to 20 minutes under a vacuum of 5 to 50 mm 10Hg. The flavor oils are then added to the mixture which is followed bymixing another 10 to 20 minutes under vacuum of 5 to 50 mm 10 Hg.

The resultant components are dentifrice compositions of a texture likethat of normal toothpastes having a pH in the range of 5 to 8,preferably 6.5 to 7.5, e.g., 7, and of satisfactory flavor.

Packaging of the Dual Component Dentifrice

The dual component composition of the present invention is packaged in asuitable dispensing container such as a tube or pump in which thecomponents are maintained physically separated and from which theseparated components may be dispensed synchronously. Such containers areknown to the art. Examples of suitable pump devices are disclosed inU.S. Pat. No. 4,528,180 and U.S. Pat. No. 5,332,124. Examples of asuitable dispensing tube are disclosed in U.S. Pat. Nos. 4,487,757 and4,687,663 wherein the tube is formed from a collapsible plastic web andis provided with a partition within the tube defining separatecompartments in which the physically separated components are stored andfrom which they are dispersed through a suitable dispensing outlet.

The following specific Example illustrates the present invention. Theindividual dentifrice components described below were prepared byfollowing the procedure described above. The amounts of the variousingredients are by weight unless otherwise indicated. The resultantcomponents were packaged in tubes or other containers provided withmeans for physical separation of the individual dentifrice components.

EXAMPLE I

A dual component dentifrice composition having the following ingredientswas prepared:

Component A Component B Ingredients Wt. % Ingredients Wt. % Deionizedwater 10.079 Deionized water 16.0 Sodium fluoride 0.486 Sodium MFP 0.76Sodium saccharine 0.25 Sodium saccharin 0.40 Iota-carrageenan 0.735Sorbitol (70%) 19.25 Titanium dioxide 0.50 Glycerin 20.30 Sorbitol (70%)8.00 Sodium tripolyphosphate 3.00 Glycerin 17.00 Xanthan 0.50 Gantrez27.20 Laponite D 0.70 NaOH 50% solution 2.00 Zeodent-115 5.00Zeodent-165 2.00 Zeodent-165 2.00 Zeodent-115 18.65 Sylodent XWA65020.00 Flavor 1.00 Flavor 1.10 Sodium bicarbonate 10.00 Tetrasodiumpyrophosphate 2.00 Triclosan 0.60 Titanium dioxide 0.4 Sodium laurylsulfate 1.50 Tegobetaine 2.00 Polysorbate 20 2.00 Polyethylene glycol600 3.00 Papain 1.00 Glucoamylase 0.20 Lipase 0.06 Sodium bisulfite 0.10Sodium phosphate monobasic 0.03 Anhy, Na Phosphate dibasic 0.20 Total100.00 100.00

Upon use, Components A and B are combined, for example on thetoothbrush, to give a combined composition, designated as Composition“X”. Composition “X” was evaluated for its ability to control bacteriaon the back of the tongue that are responsible for oral malodorformation as well as the control of breath VSC using the Halimeter™.

The evaluation of the quantity of bacteria responsible for oral malodorwas determined in-vivo in a tongue micro-flora study. The compositionswere tested for their ability to reduce the micro-flora on the back ofthe tongue, especially those species responsible for the generation ofH₂S. The study required panelists to swab one side of the back of thetongue for bacterial collection at baseline and the alternate back sideof the tongue four hours post treatment. This was done before (baseline)and after panelists brushed with treatment products for 1 minutefollowed by swishing with the dentifrice slurry for 15 seconds. Thecollected samples were plated onto lead acetate agar media for theselection of H₂S-forming bacteria as well as blood agar media todetermine the total level of bacteria present on the tongue andincubated under anaerobic conditions at 37° C. After 72 hours,colony-forming units of H₂S-forming bacteria, and total bacterialcolony-forming units were enumerated. The mean colony forming unitresults were used to calculate percent reduction from baseline.

The results of the in-vivo tongue micro-flora study are recorded inTable I below. For purposes of comparison a clinically proven commercialtoothpaste product, containing 0.3% Triclosan, designated Composition“C”, which did not contain enzymes, was also evaluated in the study. Aplacebo dentifrice which did not contain enzymes or Triclosan was alsoprepared containing a silica abrasive and SLS surfactant. Thecomparative and placebo dentifrice results are also recorded in Table Ibelow.

TABLE I TOTAL BACTERIA REDUCTION FROM TONGUE SURFACE 5 Hours % ReductionBaseline Post Brushing from baseline Composition Mean CFU* Mean CFU ofMean CFU Placebo 6.2 10⁵ 5.4 10⁵ 14 C 3.7 10⁵ 1.4 10⁵ 63 X 1.2 10⁶ 1.210⁵ 89 CFU = Colny forming units

The results recorded in Table I indicate that the dentifrice compositionof the present invention, Composition X unexpectedly provided asubstantially reduced quantity of tongue bacteria as compared to theplacebo and the comparative dentifrice, Composition C, a clinicallyproven Triclosan containing commercial product.

EXAMPLE II

The tongue micro-flora study procedure of Example I was also done toevaluate the ability of Composition “X” to specifically reduceodor-forming (H₂S) bacteria on the back of the tongue.

The results of this second study are recorded in Table II below.

TABLE II H₂S-FORMING BACTERIA REDUCTION FROM TONGUE SURFACE Baseline 5Hours Post Treatment % Reduction Composition Mean CFU Mean CFU fromBaseline Placebo 9.8 10⁴ 5.1 10⁴ 48 C 2.4 10⁵ 8.8 10⁴ 63 X 1.4 10⁵ 2.410⁴ 83

The results recorded in Table II with respect to H₂S-forming bacteriaare consistent with the findings for the total bacteria load recorded inTable I.

EXAMPLE III

The dual component dentifrice composition of the present invention wasalso found to control volatile sulfur compound (VSC) formation inclinical breath VSC study involving the same human subjects described inExample I and Example II. Breath-odor was measured using a Halimeter™ atbaseline and at four hours after brushing the teeth for one minute andswishing the slurry for 30 seconds. The results recorded in Table Illare consistent with data represented in Table II indicating a greaterreduction in breath VSC's responsible for oral malodor when compared tocomparative compositions in which enzymes were not used in combinationwith Triclosan.

TABLE III Clinical study involving oral malodor reduction. Baseline 5Hours Post Brushing % Reduction of Composition [VSC] in ppb* [VSC] inppb Malodor Placebo 270 270 0 C 180 130 31 X 380 100 66 *ppb = parts perbillion

1-8. (canceled)
 9. A method for retarding bacterial plaque accumulationon teeth and oral malodor in the oral cavity which comprises preparing adual component dentifrice in which a first component contains a nonionicantibacterial agent and a second component contains an enzyme,physically segregating the components prior to use, simultaneouslycombining the components for application to the teeth, the componentswhen mixed upon application to teeth providing an antiplaque effect withsuperior antimalodor benefit.
 10. The method of claim 9 wherein thedentifrice contains a silica abrasive having an oil absorption valueless than 100 cc/100 g silica.
 11. The method of claim 9 wherein the lowoil absorption silica abrasive is present in the composition at aconcentration of about 5 to about 40% by weight of the composition. 12.The method of claim 9 wherein the proteolytic enzyme is papain.
 13. Themethod of claim 9 wherein the proteolytic enzyme is present in thedentifrice in combination with a lipase.
 14. The composition of claim 9wherein the proteolytic enzyme is present in the dentifrice compositionin combination with a lipase and glycoamylase.
 15. The method of claim14 wherein each of the enzymes is present in the composition at aconcentration of about 0.2 to about 5.0% by weight of the composition.